Manston airport currently runs on a skeleton crew of about 100 - the bare minimum required to handle any number of flights. Quadrupling the present number of flights wouldn’t result in a quadrupling of the present staff numbers.
The Parsons Brinckerhoff (PB) report points out that there’s plenty of staff capacity to be taken up:
[p8] Given that Manston Airport currently employs a proportionately large workforce for a small throughput, growth of passengers and freight in the short term may not necessarily lead to a significant employment and hence economic impact.
The PB report also raises a very good point which, as far as I know, has never been addressed - how much slack capacity is there, how much more traffic can Manston handle before they have to employ more people?
[p8] We would therefore like to see more evidence of the ‘threshold’ whereby Manston Airport achieves a specified level of throughput such that additional employment is required.
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